Field of the Invention
The present invention relates to an electrophotographic photosensitive member, and a process cartridge and an electrophotographic apparatus each including the electrophotographic photosensitive member.
Description of the Related Art
An electrophotographic photosensitive member containing an organic photoconductive material (hereinafter referred to as “charge generating material”) is currently a major electrophotographic photosensitive member to be used for a process cartridge or an electrophotographic apparatus. The electrophotographic photosensitive member generally includes a support and a photosensitive layer (charge generating layer and hole transporting layer) formed on the support. In addition, an undercoat layer is formed between the support and the photosensitive layer in many cases.
A charge generating material having additionally high sensitivity has been used in recent years. However, as the sensitivity of the charge generating material rises, an amount of charge to be generated increases and hence the charge is liable to reside in the photosensitive layer. Consequently, a positive ghost is liable to occur. As a technology of suppressing such positive ghost, in Japanese Patent Application Laid-Open No. 2014-029480, there is a disclosure that the undercoat layer contains a polymerized product (cured product) obtained by polymerizing a composition containing an electron transport material, a cross-linking agent, and a resin. Further, in Japanese Patent Application Laid-Open Nos. 2007-148294 and 2008-250082, there is disclosed a technology involving incorporating an electron transport material into the undercoat layer. There is also disclosed a technology involving curing the undercoat layer so that, when the electron transport material is incorporated into the undercoat layer, the electron transport material is not eluted into a solvent in an application liquid for a photosensitive layer during the formation of a photosensitive layer serving as an upper layer of the undercoat layer.